/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.drools.core.util;
import java.util.Collection;

import org.drools.core.util.Queue.QueueEntry;

public interface Queue<T extends QueueEntry> {
    void enqueue(T queueable);

    T dequeue();
    void dequeue(T activation);

    boolean isEmpty();

    void clear();

    Collection<T> getAll();

    int size();

    T peek();

    interface QueueEntry {

        void setQueued(boolean b);

        int getQueueIndex();

        void setQueueIndex(int index);

        void dequeue();
        boolean isQueued();
    }
}
